Tag Archive for: innovative solutions

Hybrid heating

LK "Green-Climate-System (GCS)" Warm Air Heater

The Climate Protection Act has been in force since August 2021.
The German government has tightened climate protection targets and enshrined the goal of greenhouse gas neutrality by 2045. By 2030, emissions are already to be reduced by 65 percent compared with 1990.

Warm air heater RBW
LK Warm air heater RBW

LK Metallwaren offers three innovative solutions for the heating, ventilation and air conditioning of production, logistics and industrial halls. In order to achieve the climate protection targets in non-residential buildings, LK Metall has combined the RBW warm air heater and the REKU ventilation system with heat pump technology , as well as developing the new “Green Climate System”, which heats industrial halls without using gas as a fuel.

LK Warm air heater RBW with condensing boiler and heat pump technology
LK Warm air heater RBW with condensing boiler and heat pump technology

The hybrid heating system with gas and heat pump technology

The very efficient RBW warm air heater with condensing technology is extended with a heat pump package. The combination of gas as a fuel and heat pumps for heat exchange creates the hybrid heating system. Here, the heat pump takes over the heat generation mainly in the transitional period, i.e. in autumn and spring. In winter, on the other hand, the gas heating only switches on when the outside temperatures are too low to heat mainly with the heat pump.

With the air-to-air heat pump, the air is used as a heat source and thus an efficient and environmentally friendly operation is realized. The heaters in the warm air heater are piped to the heat pump and filled with R32 refrigerant. Additional fan units make independent operation of warm air heater and heat pumps possible. The air-to-air heat pumps used with the new R32 refrigerant significantly improve energy efficiency.

Comparison of the greenhouse potential of refrigerants
Graphic - Global Warming Potential (GWP) over 100 years
Graphic – Global Warming Potential (GWP) over 100 years
Source: IPCC Fourth Assessment Report. Global Warming Potential (GWP) over 100 years.

Compared: 2,088 (R410A) vs. 675 (R32). The advantages of hybrid heating are obvious. Hybrid heating reduces CO2 emissions by up to 30%, significantly reducing the need to burn fossil fuels. Another advantage of hybrid heating is the cooling function, which is provided by the heat pumps at all times. Especially in summer, this additionally improves the hall climate for the staff. LK hybrid heating is used in production and logistics halls. In the case of renovation, a gas hybrid heating system is subsidized by BAFA with up to 30 %.

The ventilation system REKU combined with heat pump technology

The LK ventilation systems REKU are often used in aerosol polluted production areas such as machining fabrications, welding shops and areas with high process waste heat. Filtrations up to class F7 ( New: ISO ePM 2.5) can be used in supply and exhaust air. The filter class can be adjusted depending on the application. With the integrated heat recovery system, up to 84% of the thermal energy contained in the exhaust air is transferred to the supply air via a plate heat exchanger using the counterflow principle. The outside air drawn in is thus heated and fed into the hall. With this technology, the supply air and exhaust air flow is separated from each other. Thus, heat from polluted air can also be used.

LK Ventilation system REKU with heat pump package
LK Ventilation system REKU with heat pump package

In summer, the process waste heat is discharged directly to the outside. The heat recovery is bypassed via a bypass to avoid unnecessary heating. A combination of the LK ventilation system REKU and an air-to-air heat pump does not require fossil fuels. As with the other system combinations with heat pumps from LK Metallwaren, the heating element can be operated for heating (direct condenser) or for cooling (direct evaporator). This added value helps to significantly improve the hall climate. Another advantage is that this combination is also subsidized by up to 35%.

The LK Warm Air Generator Green Climate System
The LK Warm Air Generator Green Climate System

The new LK “Green-Climate-System” (GCS) warm air heater

In order to conserve finite resources, the LK design engineers have developed the new CO2-neutral LK “Green-Climate-System (GCS)” Warm Air Heater developed for industrial halls from 4 m hall height. The “Green Climate System” does not use fossil fuels. The LK warm air heater is installed under the hall roof and draws in either hall air or outside air. Ventilation is provided by highly efficient radial impellers with EC motor technology. The passing air is heated via a heating coil connected to the heat pump. An upstream filter cleans the fresh and hall air supply from impurities. In case of very cold outdoor temperatures, it is possible to use an electric reheating coil. This covers peak loads without having to resort to a fossil fuel.

The system behaves similarly to the heating element in the heat pump in the domestic sector. Here, as in the systems already mentioned above, a heat pump with R32 coolant is used. The new system can thus heat and ventilate the hall during the winter months. In summer, ventilation and cooling is possible. With the new LK warm air heater “Green-Climate-System”, LK Metall relies 100% on the medium electricity and thus on regenerative energy sources. This makes the new plant system particularly eligible for subsidies.

Conclusion: LK Metall relies on energy efficiency and resource-saving systems with its entire plant technology in hall heating.

 

The new office building of mister*lady GmbH in Schwabach (photo source: LK Metall)

Dust-free feel-good climate without drafts on 4,500 sqm

The German fashion retailer mister*lady relies on energy-efficient heating without dust and drafts. LK Metall installed an innovative heating and ventilation system as part of a new construction of a logistics center for the German fashion retailer mister*lady in Schwabach. An investment that has already proven itself in many ways, emphasizes mister*lady managing director, Rudolf Kempter.

Background: mister*lady GmbH moved its headquarters from Nuremberg to Schwabach. In addition to the new central administration with an area of 6,000 m², two logistics halls with an area of 4,500m² each were built. Each hall has 10 gates, a room height of about 7.50 m and a room volume of about 75,000 m³.

In particular, the climate-friendly heating and ventilation of the logistics halls posed a challenge. Managing Director Kempter was faced with a choice. “The architect, general contractor and other consultants recommended different solutions,” he recalls, “so with new construction, it’s important to find out exactly what the requirements are.” Of course, the warehouse activities had to be taken into account: The approximately 22 mister*lady employees moved about 15 million parts in about one million packages per year in single-shift operation. Around 3,600 arrivals and departures took place at the 10 loading stations.

Since the production halls employ the company’s own staff, Kempter is particularly concerned about their well-being: “A modern and energy-efficient solution was important. To achieve a good indoor climate for our people, the temperature distribution must be even and free of dust and drafts. Rudolf Kempter deliberately decided against using gas-fired dark radiators.

Technical structure of the hot air generators
The warm air generators installed under the ceiling draw in waste heat rising from the hall – such as heat generated by lighting or solar radiation – and filter it. In addition, fresh outside air can be drawn in. The air passes a stainless steel combustion chamber to bring it to the desired room temperature. Turbulent flow of the exhaust gases is generated inside the heat exchange tubes arranged on the left and right, thus ensuring optimized heat exchange. Special air outlets and return air ceiling fans distribute the air flow draught-free in the hall. The hot air distribution is controlled automatically by means of PI differential temperature control via measuring sensors in the working area and on the ceiling.

A control system regulates the temperature of the system intelligently and adapted to the wishes of mister*lady: The hall is heated individually as required. The desired room temperature is freely programmable. After an installation period of only one week, mister*lady was able to put the systems into operation.

Costs in view
Looking back, after a first winter heating season, the managing director’s expectations have been met: “The employees are satisfied. The air layering is super, as promised. The air is distributed evenly. There are no cold or warm corners, no trace of drafts.” The energy consumption is also convincing: “On normal working days, we need an average of 320 m³ of gas during the cold season, which corresponds to a cost of about €80,” says Rudolf Kempter.

Especially in the transitional period, the system does not require the burner to be switched on. Then the accumulated heat under the hall roof is already enough. The return air ceiling fans then distribute it evenly back to where it is needed. Great climate should also prevail in the summer at mister*lady. Here, the good hall insulation and the ventilation system play the supporting role. At night, the system draws in the cold outside air and has already ensured pleasantly cool temperatures in the logistics hall by the time the shift begins in the morning. This makes extra air conditioning superfluous.

Advantage: less space required for hall expansion
Another advantage of the plant will only come into play in the future. Rudolf Kempter has further plans for the expansion of the hall. He would like to add a lattice mezzanine at mid-hall height for administration. No problem thanks to the intelligent air distribution of the RBW 125. “With our heating solution, even the employees on the first floor still get warm feet. In addition, there is no need to maintain a minimum distance, as is required for radiant heaters. The space consumption would have been enormous with probably up to 70 radiant heaters needed in the logistics area,” he concludes.

 

Warm air heater RBW - Gentle temperatures on 7,700 sqm

Three different temperature ranges for sensitive goods

Euphoniums, cajons and agogos – all these wonderful musical instruments can be found in Treppendorf in the Steigerwald in the 7,700 square meter logistics halls of the Thomann music store. In total, there are about 24,000 items here – from guitars and pianos to stringed instruments and various types of percussion instrument.

“We need a special indoor climate for storing musical instruments,” explains Stefan Thomann, co-founder and project manager for logistics at the music retailer. “The items are very sensitive; for example, if the humidity is too low, the tops of guitars can crack. With temperatures, constant air quality is especially crucial.”

Therefore, the company paid special attention to heating and air conditioning technology. Stefan Thomann: “For the pallet warehouse, we only had low temperature requirements because employees are not permanently working here. In the small parts storage area, on the other hand, we were aiming for a temperature of 16 to 17 degrees. But for incoming goods, it had to be a little warmer. The challenge with the technology: despite the three different temperature areas, it is one large, continuous hall.” This three-part temperature concept was realized by LK Metall. Two RBW direct-heated warm air generators with integrated mixed air equipment were used in the pallet and small parts warehouse, which were mounted on the hall ceiling between the two areas. An RBW warm air heater with integrated mixed air unit was also installed in the goods receiving area.

Music store Thomann
Music store Thomann

Evenly from the floor to the roof

The heating system is controlled by a building management system and several thermostats. If the temperature in one of the zones falls below a programmed set point, the respective heating system automatically turns on. Through the surface of the combustion chamber, the heat released by the burner is transferred directly to the passing air. Thus, up to 95 % of the energy used is converted directly into heat. In addition, further heat exchange of the flue gases takes place through the downstream, countercurrent heat exchange tubes, which are washed by the air flow along the entire length of the plant. At the end of the heat exchange pipes, the heated air leaves the plant via mixed air parts. Individually installed return air ceiling fans ensure uniform heat distribution over the entire height of the hall. A differential temperature control system also optimizes and reduces the temperature differences from the roof to the floor in the entire hall area to around 3 to 4 degrees.

A special feature of the system: the warm air generators can be used not only for heating, but also for ventilation. “In the summer months, the temperature in the hall is driven down by a summer night cooling system,” explains Harald Wimmer Sales Manager at LK-Metall. “This allows air temperature, air quality and air distribution to be adjusted as needed.”

Thanks to the finely tuned heating technology between the halls, the sensitive musical instruments will be safely stored in the future with regard to room temperature.

Degreasing baths pollute waste water Effectively remove oils and greases from wash liquors

Reduce wastewater loads from degreasing baths

Reducing wastewater pollution from degreasing baths while saving costs in terms of environmental protection is an important issue in electroplating plants.

The manufactured components must be degreased and freed from corrosion protection before a painting or coating process. With the light liquid separator from LK Metall, it is possible to use the contaminated wash liquor in the degreasing bath for a significantly longer period of time without additional chemicals by extreme removal of the accumulating oil.

LK light liquid separator: suitably designed for degreasing processes
LK light liquid separator: suitably designed for degreasing processes

Continuously remove oil from wash liquor

To degrease the components, they are immersed in degreasing baths and cleaned with the help of cleaning chemicals at a temperature of up to 90 °C. The oils and greases (light liquids) remain in the bath and, after a certain concentration, lead to saturation of the wash liquor. In turn, the floating oils contaminate the components and lead to a loss of quality in further processing. Suction of the oil by a simple skimmer on the surface of the wash liquor is often insufficient and too low in efficiency. Integrated into existing galvanizing processes, the easy-to-operate and low-maintenance light liquid separator from LK Metall continuously removes the oil from the wash liquor. A physically operating oil separator built into the system solves this task reliably and particularly economically. The disposal intervals are considerably extended. The oil separator guarantees high safety and long service life.

Process water treatment: degreasing with LK separator system

Process water treatment: degreasing with LK separator system

Longer service life reduces disposal cycles

Fully integrated into the ongoing production process, the service life of the degreasing bath is extended from about one week to around eight weeks. Compared to weekly disposal, this means an increase in service life of up to 8 times and thus a significant reduction in disposal cycles. An additional cost savings is achieved in the reduced load on the neutralization plant. Thus, on average, more than 100 liters of pure oil are separated within the first eight weeks after startup. At the same time, this means a substantial saving in chemicals. Adapted to the corresponding size of the degreasing bath, the LK light liquid separator can be integrated into almost any production process.